Vacuum printing frame gasket



April 9, 1946. q GLASSEY 2,398,303

VACUUM PRINTING FRAME GASKET Filed Nov. 9, 1944 FIG. 1. 1 7

\ INVENTOR W m A TTORNE YS Patented Apr. 9, 1946 vacuum ram'rmc. mama ossxar Courtney Q. Glasaey,

Rochester, N. Y., minor to tman Kodak Company, Rochester, N. Y., a

corporation of 8 Claims.

This invention relates to photography particularly to vacuum printing frames.

ing specification, ticularly pointed thereof.

At the present time it is diflicult to obtain rubber gaskets for vacuumprinting frames, and it is likewise diflicult to obtain suitable gaskets for the many diiferent sized printing frames now in use, the gaskets being made of a suitable rubber Most vacuum printing frame gasable for use in making vacuum gaskets as, for instance, Vinylite, preferably with considerable New Jersey Application November 9, 1944, Serial No.

Fig. 2 is a transverse section taken on line 22 on Fig. 1;

Fig. 2A is an enlarged fragmentary sectional view of an edge of my improved form of gasket largest size of in the gasket;

Fig. 3 is an enlarged bottom plan section of a preferred form of gasket:

Fig. 4 is an enlarged transverse section through the strip gasket material and taken on line 4-4 of Fig. 3:

Fig. 5 is an enlarged fragmentary section, through a vacuum line connection this view being taken on line 5-5 of Fig. 1:

Fig. 6 is a view similar to Fig. 3 but of a second embodiment of my invention; and

Fig. 7 is a cross section of a gasket strip constructed in accordance with a third form of my invention.

' My invention broadly comprises forming a strip of view of a I prefer to reinforce at least the main air channel in the strip so nary use.

Referring to Fig. 1, a vacuum gasket i is shown positioned on a printing frame which may consist of a glass plate 2. The frame I held by a nature that a substantially air-tight joint may result.

The strip material of which the frame I is in Fig. 4, consist of a band thick center portion ill tapering to a relatively thin edge ii at each that it will not collapse in ordiadhesive tape 8, so that the -oi projections length but which is nevertheless sumciently rigid to prevent the arched center portion In from collapsing under normal use.

The extreme edges H of the strip are provided with fiat portions ll along the entire length of the strip, these flat portions shown so as to lie in a plane. From the flat portions the ribs I! extend inwardly, as shown in Fig. 3, to the inverted channel It. Like the edges 14, the ribs i! are also adapted to normally lie, in a plane; but like the edges i4 they may lie fiat'on layers of material such as sensitized material, negative material, and the like, when these materials areplaced on the glass plate 2. The ribs I! leave air channels l8 between them so that when air is evacuated from the main channel i2, air may also pass through the transverse channel to leading to the main channel l2.

As indicated in Figs. 1 and 6, one or more of the rectangular members forming the frame i may be provided with a ferrule l1 which forms a connection between the channel l2 and a tube l8 leading to the air evacuating apparatus. Such apparatus may consist of a water aspirator, a filter pump, or a vacuum line, preferably with a vacuum reservoir.

The ferrule i1 is preferably made may be attached by an operator up his own vacuum frame from rial if he desires to do so. It may cylinder i8 of a size to fit into the nel H with a tubular member 20 wardly therefrom. The bottom surface of the ferrule 40 should rest upon the glass or film to support the gasket against the weight of the flexible vacuum line It. This surface to must pass air freely; it may be knurled or formed with cross channels M as shown. This tubular memher is threaded at 2!, and by placing a washer 22 over the threaded portion, the ferrule may be at tached in place by turning down a nut 23 on the threaded portion to clamp the parts tightly in position. The washer 22 is preferably provided with a lower surface 24 which is partially cylin dricai in shape so as to closely fit the center portion it! of the strip material. The tubular member 20 is provided with a bulbous end it of diameter less than the inside diameter of the nut 22 to receive the air evacuating tube iii.

In Fig. 8 I have shown a modified or pat tern for the strip material which may be used make a frame. in this form of my invention there is a central inverted channel similar to'channei iii in the first described embodiment of my invention. The extreme edges iii of material are edges i i in that they normally lay in a plane. it provided a plurality 341 which may be of uniform or gradually increasing height toward the channel 32, leaving transverse channels 35 and longitudi nai channels 36 between the projections. Thus, the projection 34, like the ribs l5, support the sides of the strip material awa from contact with the glass plate 2 or the material laid thereon so that air may be freely evacuated from almost' the entire cross section of the strip ma.- terial.

Referring to Fig. 2, when it is desired to make a print an operator may lay on the printing frame 2 a sheet of crinoline 31, a sensitive film 38, and a negative 39 to be printed. He may then lay the gasket i so that one side 40 of the gasket lies over so that it who can make the strip mateinelude a hemiinverted sham-- extending up the crinoline, sensitive film and negative, and so that the other side li lies against the glass plate. The aspirator or other air evacuating device is being formed as aeaaaoa then turned on so that air may be drawn through the tube It and the ferrule l1 item the inverted channel 12, thereby removing air from the interstices of the crinoline and from between the sensitive film and negative, drawing these parts into intimate contact in a well known manner. The printing frame may be then subjected to light to form an image on the sensitized material, and the vacuum line may be released, permitting the materials to be removed from the printing frame, If it is desirable to print through the plate glass 2, the same arrangement can be used except that the crinoline would not be used, the sensitized material would be placed in the middle, and the negative would be placed against the glass plate. A sheet of cellulose acetate or other relatively airprooi flexible sheet may be placed over the film and negative and air evacuated in the manner above described.

If desired, the cross section of the strip material may be unsymmetrical. The inverted channel may be anywhere between the edges and the transverse air channels on one edge may be longer than on the other or even omitted from one side. Fig. '7 shows a strip with the greatest thickness at 43 from which the thickness tapers at N toward one edge 45 and tapers at 48 toward the other edge 1. Edges 4-6 and 41 are differentially spaced from the channel 48 in the thick portion 43. Transverse channels 49 are longer than transverse channels 50. Reinforcing wire screen 5i may be used to strengthen the channel 48.

While I contemplate providing strip material from which the individual operator may make up his own vacuum gasket, I also may provide the gaskets themselves and may cement the mitered corners together rather than merely cover the corners with adhesive tape.

While I have described a preferred embodiment of my invention, it is obvious that various embodiments may be made without the parting from the scope of the appended claims.

i claim:

1. A vacuum printing frame gasket comprising a strip of flexible plastic material having a cross section tapering in thickness from thin edges inwardly to a thick portion between the two edges, an arched wall forming an inverted channel. extending through the thick portion of the strip and air passageways extending from the 1 vertcd channel toward at least one of the ed; a or the strip, the extreme edges both inciu flat surfaces adapted to lie in contact with o. supporting surface.

2. A vacuum printing frame gasket as defined in claim 1 characterized by reinforcing material supporting the inverted channel extending through the strip.

3. A vacuum printing in claim 1 characterized supporting the inverted channel extending through the strip, said reinforcing material being spaced from the outside of the arched wall for forming the inverted channel.

4. A vacuum printing frame gasket as defined in claim 1 characterized by ioraminous metallic reinforcing embedded in the arched wail forming the inverted channel.

5. A vacuum printing frame gasket comprising a strip of flexible plastic material having a cross section tapering in thickness from the center outwardly to the two edges, an arched wall forming an inverted channel extending through the center of the strip and air passageways extending from the inverted channel toward the edges frame gasket as defined by reinforcing material of the strip, the flat surfaces adapted to lie in contact with a 7. A vacuum use in holding a negative and sensitized film flat 

